jsSHA2 is an OpenSource JavaScript implementation of the Secure Hash Algorithm, SHA-256-384-512. As defined by NIST:

'All of the algorithms are iterative, one-way hash functions that can process a message
to produce a condensed representation called a message digest. These algorithms enable the
determination of a message’s integrity: any change to the message will, with a very high
probability, result in a different message digest. This property is useful in the generation and
verification of digital signatures and message authentication codes, and in the generation of
random numbers (bits)'.

It currently has a working implementation of SHA-256 that can be tested here:

Latest News

Saturday December 21st 2004

First public release of jsSHA2. It includes the SHA-256 implementation.

It's been finished and in production for over a year now, so I would call it fairly stable :)